Abstract: A method of mapping Space-Time Coding (STC) data to subcarriers in a broadband wireless communication system using multiple antennas is provided. Transmission symbols are encoded according to a predetermined space-time coding matrix and the coded data symbols are mapped to time-space-subcarriers according to a mapping rule determined by the space-time coding matrix.

Abstract: An apparatus is provided for transmitting uplink fast feedback information in a wireless communication system. In the apparatus, a channel encoder generates uplink fast feedback information to transmit, and outputs 3-bit codewords being set according to the fast feedback information. A noncoherent modulator modulates transmission symbols corresponding to the codewords using a noncoherent modulation scheme, and allocates the modulated transmission symbols to each of subcarrier bundles. An inverse fast Fourier transform (IFFT) unit IFFT-processes a transmission signal comprised of the subcarrier bundles before transmission.

Abstract: A multiple-input multiple-output (MIMO) communication system is provided for communication between a transmission apparatus having a plurality of transmission antennas and a reception apparatus having a plurality of reception antennas. The reception apparatus performs singular value decomposition (SVD) on channel information for a channel established to the transmission apparatus, and feeds back the SVD-decomposed channel information to the transmission apparatus. The transmission apparatus receives the SVD-decomposed channel information from the reception apparatus, performs QR decomposition on the received SVD-decomposed channel information, and sets multiple transmission antennas to be allocated to the channel, thereby performing beamforming.

Abstract: An Automatic Repeat reQuest (ARQ) error correction transmitting apparatus and method in a multiple antenna system are provided. In the ARQ error correction apparatus, a serial-to-parallel converter converts serial input data to parallel data, a retransmission processor determines a permutation transmission mode with respect to an initial transmission mode, in response to a retransmission request fed back from a receiver, and an STBC encoder STBC-encodes the parallel data and transmits the STBC-coded data through the transmit antennas according to the permutation transmission mode.

Abstract: Disclosed is a method for using various multiple antenna schemes in a baseband wireless access system is provided. According to the method, a downlink MAP message is constructed in order to support various multiple antenna schemes based on a multiple-input multiple output (MIMO), which is one of the multiple antenna schemes, so that compatibility with exiting MIMO technology having no MIMO feedback can be achieved and overhead occurring in transmission of an MAP information element can be reduced. Further, it is possible to efficiently support spatial multiplexing technology capable of transmitting multiple layers having different modulation and coding in a MIMO system.

Abstract: An space-time-frequency block coding (STFBC) apparatus for a transmitter with four Tx antennas is provided. An input symbol sequence is transmitted through the four Tx antennas in a predetermined method based on feedback information received from a receiver or a selected matrix with regularities, thereby improving the performance of an STFBC.

Abstract: There is provided a Multi-Input Multi-Output (MIMO) communication system including a transmitter for combining at least four transmit antennas according to each of at least two sub-channels, and transmitting space-time-coded signals and at least one receiver for receiving the signals through at least two antennas, wherein the receiver includes an antenna coordination information generator for generating and feeding back optimal transmit antenna coordination information according to said each sub-channel by means of the received signals, and the transmitter includes an antenna coordination controller for controlling coordinations of the transmit antennas according to each sub-channel based on the transmit antenna coordination information fed back from the receiver.

Abstract: A transmitter for maximizing coding gain by transmitting an input symbol sequence through a plurality of transmit antennas method according to feedback CQIs from a receiver in a 3 Tx-rate 2 communication system. In the transmitter, an S/P converter converts serial modulated data to parallel modulated data. A coder mode decider determines a transmission mode based on the channel quality indicator of each transmit antenna fed back from a receiver. A coder transmits the parallel modulated data through the three transmit antennas according to the determined transmission mode.

Abstract: An STFBC coding apparatus for a transmitter with four Tx antennas is provided. In the transmitter, an encoder generates a code symbol vector by encoding an input symbol sequence in a predetermined coding method. A grouping block permutes the elements of the code symbol vector by multiplying the code symbol vector by a permutation antenna grouping pattern selected among predetermined permutation antenna grouping patterns according to a predetermined order and outputs the permuted code symbol vector as a grouping symbol vector. An Alamouti encoder encodes the grouping symbol vector in an Alamouti scheme and transmits Alamouti-coded symbols through the four transmit antennas.

Abstract: A transmitter for minimizing a PAPR in OFDM communication system. The transmitter includes: a precoder for coding input symbols so that a signal rotation is generated, and generating a complex vector including the coded symbols; an encoder for performing a frequency-space mapping for the symbols generated as the complex vector according to a predetermined scheme; a random mapper for randomly mapping the symbols for which the frequency-space mapping has been performed on a frequency plane through at least one transmit antenna; an Inverse Fast Fourier Transform (IFFT) unit for performing an IFFT for the symbols for which the frequency-space mapping has been performed; and a gradient algorithm unit for receiving IFFTed signals from the IFFT unit and reducing the PAPR.

Abstract: A data transmission apparatus and method using a full-diversity, full-rate STBC are provided. In the data transmission apparatus, a serial-to-parallel converter converts an input bit stream to parallel binary vectors. A bit/symbol mapper generates modulator input symbols by combining the bits of the binary vectors. A modulator modulates the modulator input symbols to complex symbols. A transmit matrix block encoder encodes the complex symbols using a transmit matrix and transmits the coded symbols through corresponding transmit antennas.

Abstract: An apparatus and method for full-diversity, full-rate space-time block coding in a transmitter using two Tx antennas are provided. An input symbol sequence is STBC-encoded in a predetermined method and transmitted through the two Tx antennas.

Abstract: A space-time block coding apparatus and method in a transmitter with four transmit antennas in a system using a space-time block coding scheme, a pre-coder pre-codes an input symbol sequence by multiplying the input symbol sequence by ej?, ? being a phase rotation angle, in case of QPSK in range of 0???90, 23.5???24.5, or 65.5???66.5, in case of 16QAM in range of 0???90, 15.5???17.5 or 72.5???74.5, the pre-coded symbol sequence being reconstructed to have real and imaginary parts. A mapper generates symbol vectors by recombining the real and imaginary parts of the pre-coded symbol sequence in an interleaving scheme. A plurality of Alamouti coders encodes the symbol vectors in an Alamouti scheme and transmits the encoded symbol vectors through corresponding transmit antennas.

Abstract: A space-time-frequency block coding apparatus and method in a transmitter with three transmit (Tx) antennas are provided. An input symbol sequence is transmitted through three Tx antennas according to a permutation method using a selected transmission matrix in order to improve the performance of an STFBC.

Abstract: A space-time-frequency block coding apparatus and method in a transmitter with three transmit (Tx) antennas are provided. An input symbol sequence is transmitted through three Tx antennas according to a set method using feedback information received from a receiver or using a selected transmission matrix having regularities in order to improve the performance of an STFBC.

Abstract: A space-time block coding apparatus and method for transmitting an input symbol sequence through a plurality of Tx antennas using a channel information from the receiver in order to improve the performance of a space-time block coding (STFBC). A pre-coder pre-codes an input symbol sequence by multiplying the input symbol sequence by ej?, ? being a phase rotation angle, the pre-coded symbol sequence being reconstructed to have real and imaginary parts. A grouping mapper forms a grouping pattern based on feedback channel information received from a receiver, and generates a grouping symbol sequence by multiplying the grouping pattern by the pre-coded symbol sequence. A mapper generates symbol vectors by recombining the real and imaginary parts of the grouping symbol sequence in an interleaving scheme. A plurality of Alamouti coders encodes the symbol vectors in an Alamouti scheme and transmits the encoded symbol vectors through corresponding transmit antennas.

Abstract: A system and method for allocating an adaptive modulation and coding (AMC) subchannel in a communication system for transmitting and receiving data through at least one antenna. A receiver examines at least one channel received from a transmitter, selects antenna transmission mode based on the examined at least one channel, selects an optimum frequency band based on the selected mode, and sends feedback information including selection information to the transmitter. The transmitter receives the feedback information from the receiver and allocates a frequency band to the receiver according to the received feedback information.

Abstract: A preamble generation method and apparatus are provided for improving transmit diversity by changing a preamble structure in a broadband wireless communication system using multiple antennas based on a multiple input multiple output (MIMO) scheme. First pilot tones associated with different antennas are selected. The first pilot tones are multiplied by different first Walsh codes. Second pilot tones associated with the same antenna are sequentially selected along a frequency axis. The second pilot tones are multiplied by a second Walsh code. Preambles are generated by assigning, to at least two symbol durations, output signals multiplied by the first and second Walsh codes. Consecutive pilot tones during each of the at least two symbol durations are spaced by one pilot tone, and code streams of the first and second Walsh codes are alternately multiplied by the pilot tones. The preamble structure has orthogonality between the antennas using frequency, time and code domains.